​Question 1:
What is menstruation?
-Mensturation is the monthly discharge of the blood and menses from the uterus via the vagina.

Question 2:
State the hormones involved in menstruation and where they are produced. You can present your answer in any appropriate manner you seem fit.
-FSH (Follicle stimulating hormones). It is produced in the pituitary gland.
-LH (Luteinising hormone). It is produced in the pituitary gland.
-Oestrogen and Progesterone are produced in the corpus luteum, and the oestrogen also produced in the ovary.


Question 3:
Explain the stages on the menstrual cycle. Include the timeline and hormones involves where necessary. Explain each stage in detail. You can present your answer in any appropriate manner you

  • Menstrual flow stage (Day 1-5) : The uterine lining breaks down and flows from the uterus out of the body. The pituitary gland then secretes the follicle stimulating hormones (FSH).
  • Follicle stage (Day 6-13) : FSH stimulates follicle development, and usually one follicle matures into a Graafian follicle. FSH then stimulates follicles to secrete oestrogen. Oestrogen cause the repair and growth of the uterine lining. The uterine lining will become thick and spongy with blood vessels.If there's a high concentration of oestrogen in the blood, it will inhibit FSH production and stimulate the pituitary gland to secrete LH.
  • Fertile period (Day 11-17) : Sperm can survive about 2-3 days in female's reproductive system.
  • Ovulation (Day 14) : LH causes ovulation. LH also causes the formation of corpus luteum. The corpus luteum secretes progestorone.
  • Corpus Luteum Stage (Day 18-28) : Progesterone maintains the thickness of the uterine lining, preparing it for the fertilized egg. Progesterone inhibits ovulation and FSH production.

Meenushree|Bharathi
Assignment 1:

1. What is DNA?
Deoxyribonucleic Acid
DNA is a molecule which carrys genetic information.
2. How is DNA organized inside the cells?
Each DNA consists of two parallel strands. The two strands are twisted around each other to form a double helix.
A molecule of DNA is wrapped around proteins to form a chromatin thread. When the chromatin threads are wrapped tighter, they become chromosomes.

3. What is gene?
A gene is a small segment of DNA which controls the fomation of a single protein.
4. What is the basic unit of DNA and what is it made up of?
The basic unit of DNA is nucleotide. It is made up of deoxyribose , phosphate,nitrogen containing bases.
5. State the rules of base pairing.
Adenine pairs with Thymine. Cytosine pairs with Guanine.

Assignment 2:

1. Explain the process of transcription.
DNA must be unzipped to exposed the template DNA strand. The message of the gene on the template DNA must be copied into a RNA molecule called mRNA. The copying process is known as transcription.

2. Explain the process of translation.
Translation is a process whereby the mRNA leaves the nulceus and attaches to a ribosome in the cytoplasm.


Heredity Assignment 1:

1. Define genes
A gene is a small segment of DNA which controls the formation of a single protein such as enzyme.

2. Define alleles
Alleles are different forms of same gene.

3. Define chromosomes
A chromosome is a rod-like structure, visible in nucleus during cell division.

4. Define homologous chromosomes

  • Exist in pairs, one chromosome in the pair comes from the male parent and one from the female parent.
  • are similar in shape and size.
  • have exactly the smae order of sequence of gene loci. The alleles in those gene loci may not be the same.

5. Define heterozygous chromosome
A pair of alleles is different for a trait.

6. Define phenotype
A trait which can be seen. For example: the outward appearance or visible trait of an organism.

7. Define genotype
Genetic make-up of an organism, that is, the combination of genes in an organism.